Improvement in balance slide-valves for steam-engines



'suspending a slide-valve @anni (tijm.

D. n.. FRASER; or cHrcAeo; 1LLiNoIs,. Ass1GN{oR To-HIMSEL'F .AND P.' w. earns, or

SAME PLAGE.

Leam- Pama No. 92,599, dated July 13, 1869.

Thje'S'chedule referred to iu these-Letters-Patent and making pari: of 'the same.

Ta all whom 'it ma/y conctm':

Be it known that I, D, RFRAsEn, of Chicago, in the county of Cook, and State of Illinois, have invented a new and improved Self-Adjusting A nti- Eric.

tion Slide-Valve; and, Ido hereby declare that the following is a full, clear, and exact description thereof, reference being had "to the accompanying drawings, making part of this specification, in' which- Figure 1,'sheet 1, isa section taken longitudinally and vertically through the valve-chest and portions of the valvesupporting devices.

Figure 2',.sl1eet 1, is atop view of the parts, with the back plate of the valve-chest removed.

Figure 3, sheet 2, is across-'section taken through the valve and valve-chest, in the vertical plane indcated by line a: :c in fig. 2.

mmilr letter 0f .reference indicate corresponding parts in the several figures. i V This invention relates to an improvement on the D- slide valves, and is designed to relieve the valve from egccessive pressure of steam, and at the same time to suspend it from anti-friction rollers.

I am aware that Letters 'Patent ofthe United States have been granted to R. C. Bristol and others for arranging reciprocating slide-valves of the D-form upon anti-friction rollers, with the View of relieving the valve in some degree from undue pressure upon its' seat, and, therebrc, I do notl claim, broadly, this principle or mode of supporting valves.

The nature of my invention consists in devices for upwardly-.hy the `action of steam in the steam-chest, in combination with anti-friction rollers, arranged so as to relieve the valve from undue friction' at its points ef suspension from said disk, as'wiil'be hereinafter eX- plained. j

To enable others skilled'in the art to understand my invention, I will describe its -construction and-operation.

In the accompanying drawings, I have represented my improvement applied toa steam-chest, which, with: the exception oi'- its'back, ory cover A, may. be constructed and airanged'- inl the usual well-knmivn.manfner.

The cover A Ais constructed with a central -cylindrical elevation, a., rising-from it, and receiving within it the cylindrical sleeve D `ef a disk, l), between which sleeve and this elevation an annular packing-ring, c, is interposed, and capped bya stuing-boX ring, d. This prevents the escape of' steam from the chest/,around theA sleeve.

The disk D, which is represented in the drawings as from a disk which is pressed As the upper face of disk D is exposed-'tothe atmosphere, itis obvious that the internal `pressure'of lsteani lagainst. its bottoni side will tend to force it upwardly against the cover A.

The valve E is of the yD-form, and is arrangedl to slide upon the seat B, se as to allow steam to alter. nately enter. ports l), leading to the cylinder, *and eX-V haust thrcuglrport b', inuthe usual well-known .man-A DBI.

0n thevba'ck of this Devalve, two parallel jaws, G G, are constructed, which receive between themthe inverted l 'shaped pendant d D2 D2, and als anti-friction rollers gf g.

These rollers g' are arranged between the overhang` ing lips of the jaws G Gl and the shelves D2 D?, so that said overhanging portion will bear. upon the rollers and in this manner suspend the valve E -bythe said shelves. j

The rollers g', on each shelf, are'connected by their respective shafts to an oblong ame, g, which'ame is free to move, in a direction 'with its length, between the stops'df d', at the extremities of each shelf D2, and those surfaces which 'mpinge against the said 'rollers are faced with steel, as indicated at e e,inv iigs 1 and 3.

F F are valve-rods, applied to valve Evin any suitable manner, and carried out through stuffing-boxes, apf plied tc thev end of the steamchest.-

It will be seen from the above description that steam, acting upwardly against the disk l), will have a tendency to lift the valve-19, by. counteracting, to a certain extent, thepressure of 'steam acting upon lthe back of the valve. In this way, undue pressure ofthe valve is prevented. Y

Itwill Valso be seen that the valve is .suspended om the said disk D, with antiffriction rollers interposed, so as to afford bearings -for the-valve, and thereby relieve it 'of undue `friction` at its points of suspen-V It will furthermore be seen thatthe said suspension-disk D is formed on a sleeve, Dl, which rises through lthe cover A-oi. the valvechest, and is' packed steam-tight, but not held rigidly in place'. This arrangement will allow the valve to be self-adjusting, and -tocompensate for'. a wearing. awayof its face and seat.

These' features, arranged as I have shown and described, or in any othereq 'valent manner, enable me to produce an anti-friction,.self-adjusting slide-valve, which isfree irom objections attending other attempts to 4,arrive at the above-named results.

Having described my invention, i

What I claim: as new, and desire to secure by Letters latent,r is K 1. .The -selfladjusting device D- D2, with its other parts, constructed' and adapted for sustaining the valve E,'in the manner substantially as described.

2. The 'construction of the valve so that'it may be counterbalancingfdevice D and anti-'icton rollers suspended upon rollers arranged upon external flanges y', all constructed and arranged substantially as de- D, in the manner substantially deseribed.4 scribed.

3. The combination and arrangement of the anti- D. B. FRASER.

friction rollers g, Jaws, G, on valve E, shelves D2, and Witnesses:

disk D, substantiallyas described. A. D. STUR'IEVANT,

4. The combination, lvn'th the slide-valve E, of the G. J. CORSE. 

